The present disclosure relates generally to wide band array antennas and, more particularly, to a low profile, ultra-wide band, low frequency modular phased array antenna with a coincident phase center.
Ultra-wideband (also known as UWB, ultra-wide band and ultraband) is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum (e.g., greater than 500 MHz or 20% of fractional bandwidth). UWB has traditional applications in non-cooperative radar imaging with recent applications targeting sensor data collection, precision locating and tracking applications.
Unlike conventional radio transmissions that transmit information by varying power levels, frequencies and/or sinusoidal wave phases, UWB transmission systems transmit information by generating radio energy at specific time intervals and by occupying a large bandwidth to thus enable pulse-position or time modulation. The information can also be modulated on UWB signals (pulses) by encoding the polarity of the pulse, its amplitude and/or by using orthogonal pulses. UWB pulses can be sent sporadically at relatively low pulse rates to support time or position modulation, but can also be sent at rates up to the inverse of the UWB pulse bandwidth.